Anti-Cheating quill

"It was swelteringly hot, especially in the large classroom where they did their written papers. They had been given special, new quills for the exams, which had been bewitched with an Anti-Cheating spell." - (PS16)

Students at Hogwarts are given quills charmed with Anti-Cheating spells for doing written exams. (PS16)

Although not mentioned frequently throughout the series, it is presumed that students are required to use these quills during all examinations of their schooling career.